As far as I know, the bottom tube and rest of the gun is the same, so you'd probably only need a new top tube and all the stuff, like barrel, bolt, top tube and feedneck. I also believe you can just get those parts from Gog, if they still have them.

I thought that the "special parts" needed were to convert the .68 to .50...
So, I heard that all you needed to do was pull out a .50 (breech area) part and then it would be a .68. Is this not the case?
I would be curious to find out and confirm this.

Also, if you could take photos (of the parts) and document your conversion...and share them here with us...that would be awesome!!

As far as I know, the bottom tube and rest of the gun is the same, so you'd probably only need a new top tube and all the stuff, like barrel, bolt, top tube and feedneck. I also believe you can just get those parts from Gog, if they still have them.